>>33474725Red++ borrows from FRLG, Polished Crystal borrows from HGSS, an Emerald overhaul should borrow from ORAS. That means map tweaks (from the flowers in Oldale to the changed colors in Lavaridge), new locations (Sea Mauville, expanded Scorched Slab, Soaring-only locations (they could be accessible by exploring routes, or Rock Climb, or something), Lisia, Cosplay Pikachu, Mega Evolutions, post-Champion battle with your rival, etc. But of course don't borrow ORAS's fuckups like removing the Battle Frontier. And fix the standard complaints about RSE (Pomeg glitch, NPCs that are too easy/hard, too many water encounters, pic related). Beyond that, add an original touch to the game. Cameos from other generations, continuity nods like
https://bulbapedia.bulbagarden.net/wiki/List_of_cross-generational_references, anything you're inspired to add that fits with the atmosphere of the original. (Personally I'd like a snowy area somewhere.)